Email authentication just got a whole lot more important. When Gmail and Yahoo dropped their new sender guidelines for bulk email senders in 2024, the biggest changes centered around email authentication protocols. And suddenly, every email marketer’s ears perked up.
Email authentication protocols help email service providers (ESPs) identify you—yes, the brand behind those email campaigns—as a legitimate sender. It gives ESPs confidence that you are who you say you are. That your emails are legitimate, and deserve to go to the subscriber’s inbox.
What if you don’t have email authentication protocols set up? Be ready to land in the spam folder. Basically, email authentication is not just your responsibility. You do it to improve your email deliverability.
Let’s look deeper at email authentication and why it matters more than you might think.
What is Email Authentication?
I know, I know. “Email authentication” sounds like developers speak. Technical, boring, possibly involving code that makes you daydream. But if you’re an email marketer or a brand counting on email to drive results, this is the stuff you need to care about.
According to an Email Mavlers infographic—email marketing trends, 2025, email marketing experts urge brands to double down on authenticating their emails as deliverability becomes non-negotiable in 2025.
Email authentication helps ESPs identify you as a legitimate sender. It authenticates or validates your email’s legitimacy. And confirms to email servers that the message comes from the domain it says it does—and that it hasn’t been faked before reaching the inbox.
This helps email servers confirm that the message reallyThis helps email servers confirm that the message really comes from the domain it says it does—and that it hasn’t been altered or faked before reaching the inbox.
Suddenly, Gmail and Yahoo’s stricter authentication requirements make perfect sense, right?
Here’s why it matters— authentication protects you and your email recipients from spammers. These shady senders impersonate your domain, pretending to send email from your domain. That’s phishing, and it’s up 49% since 2021.
Phishers do this to trick your customers into giving away account details, passwords, and other sensitive information they can monetize. Beyond being terrible for customers, this kind of spoofing erodes trust in your emails and your brand as a whole.
ESPs and email servers refer to email authentication protocols to decide whether to accept your message for delivery at all. And whether it gets sent to spam or delivered to your subscribers’ inbox.
The three main email authentication protocols you must consider—
- Sender Policy Framework (SPF)
- DomainKeys Identified Mail (DKIM)
- Domain-based Message Authentication, Reporting and Conformance (DMARC)
For bulk senders wanting to have inbox placement with major email providers, implementing SPF, DKIM, and DMARC is essential. Whereas Brand Indicators for Message Identification (BIMI) can be seen as an extra enhancement.
Email Authentication Is Complex. Why Do That?
While email authentication sounds about as fun as filing taxes, anything you can do to build trust that leads to happier, more engaged subscribers is worth all the effort.
- Keeps Your Brand From Being Spoofed
By setting up email authentication, you:
- Ensure genuine email messages don’t get spam-flagged.
- Prevent spammers from impersonating your organization.
For example, During the COVID-19 pandemic, healthcare organizations became prime targets for email phishing. Cybercriminals impersonated trusted institutions, sending emails asking for donations. People were fooled into giving away personal info, and that led to email addresses and passwords being leaked online
Within a week of implementing DMARC, spoofed emails dropped by 70%. And within a few weeks, they stopped.
- Protects Your People From Security Threats
Your subscribers trust you enough to give you their data. If you do not authenticate your emails, scammers can use them to spoof your email address and emails to send fraudulent messages.
They use sophisticated email designs to conceal suspicious elements and make them appear harmless. Such shady emails house malicious links or attachments. When subscribers open them, it installs malware on their devices. This jeopardizes the security of their data or takes them to a dangerous site. Or data leakage and loss of confidential information.
Using established authentication protocols such as SPF, DKIM, and DMARC, brands safeguard their domains from spammers’ nefarious uses. The overall security and integrity of their email communications improves. And builds stronger relationships with recipients.
Matthew Vernhout, Principal Email Advisor at Email Industries, puts it this way–
“Taking proactive steps to protect your brand from spoofing or impersonation is now required. In the past, these were strong recommendations. Mailbox providers are dealing with more spam than ever before. Authentication of brands of all sizes helps keep your mail from being abused by others and protects your consumers and employees from abuse.”
- Supports a Good Sender Reputation
ESPs size you up and assign a reputation score–sender reputation. It’s like a credit score for your email sending habits.
This score helps decide if your email goes to the inbox or the spam folder. The higher your reputation score, the more ESP trusts you, and your emails will likely reach your customers’ inboxes.
Sure, following clean email authentication practices is formidable. But you must strengthen it to send the right signals to ESPs. Your brand’s digital trustworthiness can impact your sender reputation and in a good way.
Most important, authenticated emails make your subscribers trust them and engage with its content.
- Improves Email Deliverability
Consistently authenticated emails have better deliverability. When your emails pass ESPs authentication checks, they are less likely to be spam-flagged or rejected.
Without proper authentication protocols, even the most ingenious campaigns may never reach your audience.
- Leads to Better Inbox Placement
Inbox placement indicates the number of emails that reach the primary inbox after being successfully delivered.
Inbox placement matters because if your emails land in folders other than the main folder, say spam, newsletter, promotion, or social, recipients won’t see them as often. And your open, click-through, and conversion rates will plummet.
The stronger your authentication, the more ESPs trust you, and you will likely have better inbox placement rates.
- Keeps You Compliant and Legally Protected
Someone spoofing your domain for frauds can get you in legal trouble. Be ready to answer tough questions about your security practices. Key regulatory frameworks, like EU’s General Data Protection Regulation (GDPR) and the CAN-SPAM Act, mandate businesses to authenticate emails to regulate data privacy.
So, authenticate your emails to comply with these regulations and avoid hefty penalties.
Wrapping Up
If your email campaigns aren’t yet authenticated, now is the time to do it. By putting email authentication in place, you are shielding your brand from the potential for email fraud and helping your emails reach your subscribers.
